Chapter 1 - Living in
a Network Centric World
CCNA Exploration 4.0CCNA Exploration 4.0
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Overview
• Describe how networks impact our daily lives.
• Describe the role of data networking in the human network.
• Identify the key components of any data network.
• Identify the opportunities and challenges posed by
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• Identify the opportunities and challenges posed by
converged networks.
• Describe the characteristics of network architectures: fault
tolerance, scalability, quality of service and security.
• Install and use IRC clients and a Wikiserver.
Networks Supporting the Way We Live
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• Early data networks were limited to exchanging character-based
information between connected computer systems.
• Current networks have evolved to carry voice, video streams, text, and
graphics between many different types of devices.
Networks Supporting the Way We Live
The Global Community
• The creation of online communities for the exchange of ideas and
information has the potential to increase productivity opportunities
across the globe.
• As the Internet connects people and promotes unfettered
communication, it presents the platform on which to run businesses, to
address emergencies, to inform individuals, and to support education,
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• Online learning opportunities can decrease time-consuming and costly travel
yet still ensure that all employees are adequately trained to perform their jobs
in a safe and productive manner.
• Online courseware and delivery offer many benefits to businesses such as:
– Current and accurate training materials.
– Availability of training to a wide audience.
– Consistent quality of instruction.
– Cost reduction.
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– Cost reduction.
Networks Supporting the Way We Work
• The business networks evolved to enable the transmission of many different
types of information services, including e-mail, video, messaging, and
telephony.
• Today, networks provide a greater integration between related functions and
organizations than was possible in the past.
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Networks Supporting the Way We Play
• Describe ways communication over a network supports the
way we play
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What is Communication?
• Communication in our daily lives takes many forms and occurs in many
environments.
• Before beginning to communicate with each other, we establish rules or
agreements to govern the conversation. These rules, or protocols, must be
followed in order for the message to be successfully delivered and understood.
Among the protocols that govern successful human communication are:
– An identified sender and receiver
– Agreed upon method of communicating (face-to-face, telephone, letter,

• These data or information networks vary in size and capabilities, but all
networks have four basic elements in common:
– Rules or agreements to govern how the messages are sent, directed, received and
interpreted.
– The messages or units of information that travel from one device to another
– A means of interconnecting these devices - a medium that can transport the
messages from one device to another
– Devices on the network that exchange messages with each other
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The Elements of a Network
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The Elements of a Network
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